The amount of identifiable intangible assets recognized as of the acquisition date.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Goodwill and Other Intangible Assets (Accumulated Amortization of Intangible Asset Schedule) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Apr. 12, 2013
Accumulated amortization of intangible assets
Gross Carrying Amount	$ 96,561	$ 101,873
Accumulated Amortization	(25,541)	(19,118)
Net Carrying Amount	71,020us-gaap_FiniteLivedIntangibleAssetsNet	82,755us-gaap_FiniteLivedIntangibleAssetsNet
Core Deposits
Accumulated amortization of intangible assets
Gross Carrying Amount	82,323	87,533
Accumulated Amortization	(19,996)	(16,065)
Net Carrying Amount	62,327	71,468
Noncompete Agreements
Accumulated amortization of intangible assets
Gross Carrying Amount		102
Accumulated Amortization		(102)
Net Carrying Amount		0
Lease Agreements
Accumulated amortization of intangible assets
Gross Carrying Amount	238	238
Accumulated Amortization	(176)	(140)
Net Carrying Amount	62	98
Customer Relationships
Accumulated amortization of intangible assets
Gross Carrying Amount		14,000
Accumulated Amortization		(2,811)
Net Carrying Amount		11,189
Citizens Republic Bancorp
Accumulated amortization of intangible assets
Finite-Lived intangible assets acquired			84,774
Citizens Republic Bancorp \| Core Deposits
Accumulated amortization of intangible assets
Finite-Lived intangible assets acquired			70,800
Citizens Republic Bancorp \| Customer Relationships
Accumulated amortization of intangible assets
Gross Carrying Amount	14,000
Accumulated Amortization	(5,369)
Net Carrying Amount	8,631
Finite-Lived intangible assets acquired			$ 14,000